A Design study on a mixed oxide fuel sodium-cooled fast reactor core partially loading highly concentrated MA-containing metal fuel

高濃度MA含有金属燃料装荷・MOX燃料高速炉の炉心設計研究

大釜 和也   ; 太田 宏一*; 大木 繁夫 ; 飯塚 政利*

Ohgama, Kazuya; Ota, Hirokazu*; Oki, Shigeo; Iizuka, Masatoshi*

A neutronics design study for a mixed oxide (MOX) fuel Sodium-cooled Fast Reactor (SFR) core partially loading highly concentrated Minor Actinide (MA) containing fuel was conducted. To analyze preferable loading positions of highly concentrated MA-containing metal fuel, the characteristics of heterogeneous MA loading cores were evaluated assuming the amount of MA loaded to heterogeneous cores were same as that of a reference homogeneous 3% MAcontaining MOX fuel core. The cores loading MA-containing metal fuel could meet the design limitation of the sodium void reactivity of the SFR except for the one loading MA-containing metal fuel in the core center region. Based on these results, the core design was modified to maximize amount of MA transmutation. The modified core loading 60 subassemblies of 16% MA-containing metal fuel in the outermost region could attain the largest amount of MA transmutation, which was larger by about 60% than that of the reference homogeneous MOX fuel core.